First thoughts on a financial agreement

My wife and I are not sure we will continue together so we are looking at coming to a financial agreement with a view to divorce at a later date. We have two young children. My draft offer includes the CSA payment which is 20% of my net salary and I have offered 10% as a personal allowance plus 2/3 of the interest payment on the mortgage. All in all this comes to 42.5% of my net salary. We would remain equal owners of the marital home until better times to sell or one of us is bought out by the other. Having been married for only 3 years with 30 years still to retirement how much consideration is given to our pensions. Mine would be considerably more, but half our lifetime is a long way away! Any advice much appreciated. Is it as simple as a percentage per year of our marriage that can be offset against the percentage ownership of the house? Is my offer generally fair already??

Hi it seems we have a simular situation except I have been married a little longer. Im pleased to see that both parties I presume have agreed to negotiate! did you use a mediator and are you considering confirming your agreement via a solicitor? Pensions are a nightmare but as you state they are at an early stage of maturity and even if you had to loose a percentage you do have manny years to build on yours. My position is I have a 23yr pension which matures at 30yrs for the last 12yrs i have been married/together this is the total period I have known my wife. Through her solicitor she is claiming half of my 23yr pension even though I had paid in for 11yrs before I had even met her? also when in theory both of us have retired she will end up with half of my current pension and a full teachers pension I could claim a percentage of this but it only has 5 years growth.
The advice I have been given is to ensure whatever your agreement you get it confirmed and endorsed by a solicitor to protect both parties. All the best